As a power conversion apparatus, such as an inverter for converting a DC voltage to an AC voltage and a converter for converting an AC voltage to a DC voltage, there has been known a power conversion apparatus performing power conversion by a plurality of switching devices, as disclosed in Patent Document 1, for example. Patent Document 1 discloses that with the use of devices made of SiC semiconductor as main switching devices, the carrier frequency for PWM control can be increased, and the efficiency can be improved when compared with the conventional ones.
Wide band gap semiconductors, such as the above SiC semiconductor have dielectric breakdown fields approximately 10 times as high as the conventional Si semiconductors to facilitate implementation of increased breakdown voltages of the devices. Accordingly, an apparatus having the same breakdown voltage can be thinner than that using Si semiconductor. Hence, conduction loss can be minimized, and the device can be compacted.
Since the wide band gap semiconductors are operable at high speed and at high temperature (e.g., 300° C.), high speed operation can achieve high efficiency of the apparatuses as a whole, and such devices can operate under a high temperature situation caused by chip size reduction, thereby reducing the size of the apparatus.    Patent Document 1: Japanese Unexamined Patent Application Publication No. 2006-42529